Correct the order in which we cope with end-of-class-definition

semantics and improve our handling of default arguments. Specifically,
we follow this order:

  - As soon as the see the '}' in the class definition, the class is
  complete and we add any implicit declarations (default constructor,
  copy constructor, etc.) to the class.
  - If there are any default function arguments, parse them
  - If there were any inline member function definitions, parse them

As part of this change, we now keep track of the the fact that we've
seen unparsed default function arguments within the AST. See the new
ParmVarDecl::hasUnparsedDefaultArg member. This allows us to properly
cope with calls inside default function arguments to other functions
where we're making use of the default arguments.

Made some C++ error messages regarding failed initializations more
specific. 

llvm-svn: 61406

16 files changed, 124 insertions, 36 deletions

diff --git a/clang/include/clang/AST/Decl.h b/clang/include/clang/AST/Decl.h
index 8ff8aefaaff..0401c504543 100644
--- a/clang/include/clang/AST/Decl.h
+++ b/clang/include/clang/AST/Decl.h
@@ -504,6 +504,27 @@ public:
   Expr *getDefaultArg() { return DefaultArg; }
   void setDefaultArg(Expr *defarg) { DefaultArg = defarg; }
 
+  /// hasUnparsedDefaultArg - Determines whether this parameter has a
+  /// default argument that has not yet been parsed. This will occur
+  /// during the processing of a C++ class whose member functions have
+  /// default arguments, e.g.,
+  /// @code
+  ///   class X {
+  ///   public:
+  ///     void f(int x = 17); // x has an unparsed default argument now
+  ///   }; // x has a regular default argument now
+  /// @endcode
+  bool hasUnparsedDefaultArg() const {
+    return DefaultArg == reinterpret_cast<Expr *>(-1);
+  }
+
+  /// setUnparsedDefaultArg - Specify that this parameter has an
+  /// unparsed default argument. The argument will be replaced with a
+  /// real default argument via setDefaultArg when the class
+  /// definition enclosing the function declaration that owns this
+  /// default argument is completed.
+  void setUnparsedDefaultArg() { DefaultArg = reinterpret_cast<Expr *>(-1); }
+
   QualType getOriginalType() const;
   
   // Implement isa/cast/dyncast/etc.
diff --git a/clang/include/clang/AST/ExprCXX.h b/clang/include/clang/AST/ExprCXX.h
index 31dfd258334..be33eb1939d 100644
--- a/clang/include/clang/AST/ExprCXX.h
+++ b/clang/include/clang/AST/ExprCXX.h
@@ -335,7 +335,9 @@ public:
   // Param is the parameter whose default argument is used by this
   // expression.
   explicit CXXDefaultArgExpr(ParmVarDecl *param) 
-    : Expr(CXXDefaultArgExprClass, param->getDefaultArg()->getType()),
+    : Expr(CXXDefaultArgExprClass, 
+           param->hasUnparsedDefaultArg()? param->getType().getNonReferenceType()
+                                         : param->getDefaultArg()->getType()),
       Param(param) { }
 
   // Retrieve the parameter that the argument was created from.
diff --git a/clang/include/clang/Basic/DiagnosticKinds.def b/clang/include/clang/Basic/DiagnosticKinds.def
index 7675710a34b..321b2c69c51 100644
--- a/clang/include/clang/Basic/DiagnosticKinds.def
+++ b/clang/include/clang/Basic/DiagnosticKinds.def
@@ -1352,6 +1352,10 @@ DIAG(warn_value_always_false, WARNING,
 // FIXME: %2 is an english string here.
 DIAG(err_typecheck_convert_incompatible, ERROR,
      "incompatible type %2 %1, expected %0")
+DIAG(err_cannot_initialize_decl_noname, ERROR,
+     "cannot initialize a value of type %0 with an %select{rvalue|lvalue}1 of type %2")
+DIAG(err_cannot_initialize_decl, ERROR,
+     "cannot initialize %0 with an %select{rvalue|lvalue}1 of type %2")
 DIAG(warn_incompatible_qualified_id, WARNING,
      "incompatible type %2 %1, expected %0")
 DIAG(warn_incompatible_qualified_id_operands, WARNING,
diff --git a/clang/include/clang/Parse/Action.h b/clang/include/clang/Parse/Action.h
index 39de870d12d..13b3c8a2b74 100644
--- a/clang/include/clang/Parse/Action.h
+++ b/clang/include/clang/Parse/Action.h
@@ -734,6 +734,13 @@ public:
                                          ExprTy *defarg) {
   }
 
+  /// ActOnParamUnparsedDefaultArgument - We've seen a default
+  /// argument for a function parameter, but we can't parse it yet
+  /// because we're inside a class definition. Note that this default
+  /// argument will be parsed later.
+  virtual void ActOnParamUnparsedDefaultArgument(DeclTy *param, 
+                                                 SourceLocation EqualLoc) { }
+
   /// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
   /// the default argument for the parameter param failed.
   virtual void ActOnParamDefaultArgumentError(DeclTy *param) { }
diff --git a/clang/lib/AST/StmtDumper.cpp b/clang/lib/AST/StmtDumper.cpp
index f11536f9c2d..c3ce92de60b 100644
--- a/clang/lib/AST/StmtDumper.cpp
+++ b/clang/lib/AST/StmtDumper.cpp
@@ -83,12 +83,14 @@ namespace  {
     void DumpType(QualType T) {
       fprintf(F, "'%s'", T.getAsString().c_str());
 
-      // If the type is directly a typedef, strip off typedefness to give at
-      // least one level of concreteness.
-      if (TypedefType *TDT = dyn_cast<TypedefType>(T)) {
-        QualType Simplified = 
-          TDT->LookThroughTypedefs().getQualifiedType(T.getCVRQualifiers());
-        fprintf(F, ":'%s'", Simplified.getAsString().c_str());
+      if (!T.isNull()) {
+        // If the type is directly a typedef, strip off typedefness to give at
+        // least one level of concreteness.
+        if (TypedefType *TDT = dyn_cast<TypedefType>(T)) {
+          QualType Simplified = 
+            TDT->LookThroughTypedefs().getQualifiedType(T.getCVRQualifiers());
+          fprintf(F, ":'%s'", Simplified.getAsString().c_str());
+        }
       }
     }
     void DumpStmt(const Stmt *Node) {
diff --git a/clang/lib/AST/Type.cpp b/clang/lib/AST/Type.cpp
index 5909c976aa6..c70ad4af521 100644
--- a/clang/lib/AST/Type.cpp
+++ b/clang/lib/AST/Type.cpp
@@ -841,7 +841,7 @@ static void AppendTypeQualList(std::string &S, unsigned TypeQuals) {
 
 void QualType::getAsStringInternal(std::string &S) const {
   if (isNull()) {
-    S += "NULL TYPE\n";
+    S += "NULL TYPE";
     return;
   }
   
diff --git a/clang/lib/Parse/ParseDecl.cpp b/clang/lib/Parse/ParseDecl.cpp
index 16e7e774aa9..213a210b9ea 100644
--- a/clang/lib/Parse/ParseDecl.cpp
+++ b/clang/lib/Parse/ParseDecl.cpp
@@ -1811,6 +1811,8 @@ void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D,
       // ActOnParamDefaultArgument will reject the default argument in
       // C.
       if (Tok.is(tok::equal)) {
+        SourceLocation EqualLoc = Tok.getLocation();
+
         // Parse the default argument
         if (D.getContext() == Declarator::MemberContext) {
           // If we're inside a class definition, cache the tokens
@@ -1824,10 +1826,12 @@ void Parser::ParseFunctionDeclarator(SourceLocation LParenLoc, Declarator &D,
                                     tok::semi, false)) {
             delete DefArgToks;
             DefArgToks = 0;
-          } 
+            Actions.ActOnParamDefaultArgumentError(Param);
+          } else
+            Actions.ActOnParamUnparsedDefaultArgument(Param, EqualLoc);
         } else {
           // Consume the '='.
-          SourceLocation EqualLoc = ConsumeToken();
+          ConsumeToken();
         
           OwningExprResult DefArgResult(ParseAssignmentExpression());
           if (DefArgResult.isInvalid()) {
diff --git a/clang/lib/Sema/Sema.h b/clang/lib/Sema/Sema.h
index 2664c57ee4b..843e732e873 100644
--- a/clang/lib/Sema/Sema.h
+++ b/clang/lib/Sema/Sema.h
@@ -276,6 +276,8 @@ public:
   virtual void ActOnParamDefaultArgument(DeclTy *param, 
                                          SourceLocation EqualLoc,
                                          ExprTy *defarg);
+  virtual void ActOnParamUnparsedDefaultArgument(DeclTy *param, 
+                                                 SourceLocation EqualLoc);
   virtual void ActOnParamDefaultArgumentError(DeclTy *param);
   void AddInitializerToDecl(DeclTy *dcl, ExprArg init);
   void ActOnUninitializedDecl(DeclTy *dcl);
diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index d84d6adad01..c6689591769 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -888,9 +888,14 @@ bool Sema::CheckInitializerTypes(Expr *&Init, QualType &DeclType,
       if (!PerformImplicitConversion(Init, DeclType, "initializing"))
         return false;
       
-      return Diag(InitLoc, diag::err_typecheck_convert_incompatible)
-        << DeclType << InitEntity << "initializing"
-        << Init->getSourceRange();
+      if (InitEntity)
+        return Diag(InitLoc, diag::err_cannot_initialize_decl)
+          << InitEntity << (int)(Init->isLvalue(Context) == Expr::LV_Valid)
+          << Init->getType() << Init->getSourceRange();
+      else
+        return Diag(InitLoc, diag::err_cannot_initialize_decl_noname)
+          << DeclType << (int)(Init->isLvalue(Context) == Expr::LV_Valid)
+          << Init->getType() << Init->getSourceRange();
     }
 
     // C99 6.7.8p16.
diff --git a/clang/lib/Sema/SemaDeclCXX.cpp b/clang/lib/Sema/SemaDeclCXX.cpp
index 918fd2ac9a7..48373369bcf 100644
--- a/clang/lib/Sema/SemaDeclCXX.cpp
+++ b/clang/lib/Sema/SemaDeclCXX.cpp
@@ -126,8 +126,9 @@ Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc,
   //   a declaration of a variable of the parameter type, using the
   //   copy-initialization semantics (8.5).
   Expr *DefaultArgPtr = DefaultArg.get();
-  bool DefaultInitFailed = PerformCopyInitialization(DefaultArgPtr, ParamType,
-                                                     "in default argument");
+  bool DefaultInitFailed = CheckInitializerTypes(DefaultArgPtr, ParamType,
+                                                 EqualLoc,
+                                                 Param->getDeclName());
   if (DefaultArgPtr != DefaultArg.get()) {
     DefaultArg.take();
     DefaultArg.reset(DefaultArgPtr);
@@ -147,6 +148,17 @@ Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc,
   Param->setDefaultArg(DefaultArg.take());
 }
 
+/// ActOnParamUnparsedDefaultArgument - We've seen a default
+/// argument for a function parameter, but we can't parse it yet
+/// because we're inside a class definition. Note that this default
+/// argument will be parsed later.
+void Sema::ActOnParamUnparsedDefaultArgument(DeclTy *param, 
+                                             SourceLocation EqualLoc) {
+  ParmVarDecl *Param = (ParmVarDecl*)param;
+  if (Param)
+    Param->setUnparsedDefaultArg();
+}
+
 /// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
 /// the default argument for the parameter param failed.
 void Sema::ActOnParamDefaultArgumentError(DeclTy *param) {
@@ -171,16 +183,16 @@ void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
     if (chunk.Kind == DeclaratorChunk::Function) {
       for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) {
         ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param;
-        if (Param->getDefaultArg()) {
-          Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
-            << Param->getDefaultArg()->getSourceRange();
-          Param->setDefaultArg(0);
-        } else if (CachedTokens *Toks 
-                     = chunk.Fun.ArgInfo[argIdx].DefaultArgTokens) {
+        if (Param->hasUnparsedDefaultArg()) {
+          CachedTokens *Toks = chunk.Fun.ArgInfo[argIdx].DefaultArgTokens;
           Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
             << SourceRange((*Toks)[1].getLocation(), Toks->back().getLocation());
           delete Toks;
           chunk.Fun.ArgInfo[argIdx].DefaultArgTokens = 0;
+        } else if (Param->getDefaultArg()) {
+          Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
+            << Param->getDefaultArg()->getSourceRange();
+          Param->setDefaultArg(0);
         }
       }
     }
@@ -269,7 +281,8 @@ void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
     for (p = 0; p <= LastMissingDefaultArg; ++p) {
       ParmVarDecl *Param = FD->getParamDecl(p);
       if (Param->getDefaultArg()) {
-        delete Param->getDefaultArg();
+        if (!Param->hasUnparsedDefaultArg())
+          Param->getDefaultArg()->Destroy(Context);
         Param->setDefaultArg(0);
       }
     }
@@ -736,6 +749,7 @@ void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
   ActOnFields(S, RLoc, TagDecl,
               (DeclTy**)FieldCollector->getCurFields(),
               FieldCollector->getCurNumFields(), LBrac, RBrac, 0);
+  AddImplicitlyDeclaredMembersToClass(cast<CXXRecordDecl>((Decl*)TagDecl));
 }
 
 /// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared
@@ -872,7 +886,6 @@ void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) {
 void Sema::ActOnFinishCXXClassDef(DeclTy *D) {
   CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D));
   FieldCollector->FinishClass();
-  AddImplicitlyDeclaredMembersToClass(Rec);
   PopDeclContext();
 
   // Everything, including inline method definitions, have been parsed.
@@ -901,6 +914,12 @@ void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclTy *Method) {
 /// ActOnParamDefaultArgument event for this parameter.
 void Sema::ActOnDelayedCXXMethodParameter(Scope *S, DeclTy *ParamD) {
   ParmVarDecl *Param = (ParmVarDecl*)ParamD;
+
+  // If this parameter has an unparsed default argument, clear it out
+  // to make way for the parsed default argument.
+  if (Param->hasUnparsedDefaultArg())
+    Param->setDefaultArg(0);
+
   S->AddDecl(Param);
   if (Param->getDeclName())
     IdResolver.AddDecl(Param);
@@ -1871,7 +1890,11 @@ bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) {
   if (Op != OO_Call) {
     for (FunctionDecl::param_iterator Param = FnDecl->param_begin();
          Param != FnDecl->param_end(); ++Param) {
-      if (Expr *DefArg = (*Param)->getDefaultArg())
+      if ((*Param)->hasUnparsedDefaultArg())
+        return Diag((*Param)->getLocation(), 
+                    diag::err_operator_overload_default_arg)
+          << FnDecl->getDeclName();
+      else if (Expr *DefArg = (*Param)->getDefaultArg())
         return Diag((*Param)->getLocation(),
                     diag::err_operator_overload_default_arg)
           << FnDecl->getDeclName() << DefArg->getSourceRange();
diff --git a/clang/lib/Sema/SemaExpr.cpp b/clang/lib/Sema/SemaExpr.cpp
index 4088f443f75..d65c10bb50c 100644
--- a/clang/lib/Sema/SemaExpr.cpp
+++ b/clang/lib/Sema/SemaExpr.cpp
@@ -1507,16 +1507,17 @@ Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
     QualType ProtoArgType = Proto->getArgType(i);
     
     Expr *Arg;
-    if (i < NumArgs) 
+    if (i < NumArgs) {
       Arg = Args[i];
-    else 
+
+      // Pass the argument.
+      if (PerformCopyInitialization(Arg, ProtoArgType, "passing"))
+        return true;
+    } else 
+      // We already type-checked the argument, so we know it works.
       Arg = new CXXDefaultArgExpr(FDecl->getParamDecl(i));
     QualType ArgType = Arg->getType();
-    
-    // Pass the argument.
-    if (PerformCopyInitialization(Arg, ProtoArgType, "passing"))
-      return true;
-    
+        
     Call->setArg(i, Arg);
   }
   
diff --git a/clang/test/SemaCXX/condition.cpp b/clang/test/SemaCXX/condition.cpp
index d611364cf03..43117e61c38 100644
--- a/clang/test/SemaCXX/condition.cpp
+++ b/clang/test/SemaCXX/condition.cpp
@@ -16,8 +16,8 @@ void test() {
   for (;s;) ; // expected-error {{expression must have bool type (or be convertible to bool) ('struct S' invalid)}}
   switch (s) {} // expected-error {{statement requires expression of integer type ('struct S' invalid)}}
 
-  while (struct S {} x=0) ; // expected-error {{types may not be defined in conditions}} expected-error {{incompatible type}} expected-error {{expression must have bool type}}
-  while (struct {} x=0) ; // expected-error {{types may not be defined in conditions}} expected-error {{incompatible type}} expected-error {{expression must have bool type}}
+  while (struct S {} x=0) ; // expected-error {{types may not be defined in conditions}} expected-error {{cannot initialize 'x' with an rvalue of type 'int'}} expected-error {{expression must have bool type}}
+  while (struct {} x=0) ; // expected-error {{types may not be defined in conditions}} expected-error {{cannot initialize 'x' with an rvalue of type 'int'}} expected-error {{expression must have bool type}}
   switch (enum {E} x=0) ; // expected-error {{types may not be defined in conditions}} expected-error {{incompatible type}}
 
   if (int x=0) { // expected-note {{previous definition is here}}
diff --git a/clang/test/SemaCXX/constructor.cpp b/clang/test/SemaCXX/constructor.cpp
index 536593d5120..68099ecac96 100644
--- a/clang/test/SemaCXX/constructor.cpp
+++ b/clang/test/SemaCXX/constructor.cpp
@@ -1,5 +1,4 @@
 // RUN: clang -fsyntax-only -verify %s 
-
 typedef int INT;
 
 class Foo {
@@ -37,3 +36,7 @@ struct y {
   y(int);
 };
 extern y b;
+
+struct Length {
+  Length l() const { return *this; }
+};
diff --git a/clang/test/SemaCXX/copy-initialization.cpp b/clang/test/SemaCXX/copy-initialization.cpp
index 5ef84de9acd..e380cc1ad3c 100644
--- a/clang/test/SemaCXX/copy-initialization.cpp
+++ b/clang/test/SemaCXX/copy-initialization.cpp
@@ -13,5 +13,5 @@ void f(Y y, int *ip, float *fp) {
   X x1 = y; // expected-error{{no matching constructor for initialization of 'x1'; candidate is:}}
   X x2 = 0;
   X x3 = ip;
-  X x4 = fp; // expected-error{{incompatible type initializing 'x4', expected 'class X'}}
+  X x4 = fp; // expected-error{{cannot initialize 'x4' with an lvalue of type 'float *'}}
 }
diff --git a/clang/test/SemaCXX/default1.cpp b/clang/test/SemaCXX/default1.cpp
index 286be6106b1..28444207d86 100644
--- a/clang/test/SemaCXX/default1.cpp
+++ b/clang/test/SemaCXX/default1.cpp
@@ -26,4 +26,6 @@ struct Y {
   explicit Y(int);
 };
 
-void k(Y y = 17); // expected-error{{incompatible type in default argument}}
+void k(Y y = 17); // expected-error{{cannot initialize 'y' with an rvalue of type 'int'}}
+
+void kk(Y = 17); // expected-error{{cannot initialize a value of type 'struct Y' with an rvalue of type 'int'}}
diff --git a/clang/test/SemaCXX/default2.cpp b/clang/test/SemaCXX/default2.cpp
index 863ac0e25fd..c2873af3f08 100644
--- a/clang/test/SemaCXX/default2.cpp
+++ b/clang/test/SemaCXX/default2.cpp
@@ -103,8 +103,20 @@ public:
     Z z2;    // expected-error{{no matching constructor for initialization}}
     Z z3(z);
   }
+
+  void test_Z(const Z& z) {
+    Z z2(z); // expected-error{{no matching constructor for initialization of 'z2'}}
+  }
 };
 
 void test_Z(const Z& z) {
   Z z2(z); // expected-error{{no matching constructor for initialization of 'z2'}}
 }
+
+struct ZZ {
+  void f(ZZ z = g()); // expected-error{{no matching constructor for initialization}}
+
+  static ZZ g(int = 17);
+
+  ZZ(ZZ&, int = 17); // expected-note{{candidate function}}
+};